/*
 * MIT License
 *
 * Copyright (c) 2023 北京凯特伟业科技有限公司
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.je.bpm.engine.impl.bpmn.diagram;

import javax.xml.namespace.NamespaceContext;
import javax.xml.xpath.XPath;
import java.util.*;
import java.util.Map.Entry;

/**
 * XML {@link NamespaceContext} containing the namespaces used by BPMN 2.0 XML documents.
 *
 * Can be used in {@link XPath#setNamespaceContext(NamespaceContext)}.
 */
public class Bpmn20NamespaceContext implements NamespaceContext {

    public static final String BPMN = "bpmn";
    public static final String BPMNDI = "bpmndi";
    public static final String OMGDC = "omgdc";
    public static final String OMGDI = "omgdi";

    /**
     * This is a protected filed so you can extend that context with your own namespaces if necessary
     */
    protected Map<String, String> namespaceUris = new HashMap<String, String>();

    public Bpmn20NamespaceContext() {
        namespaceUris.put(BPMN, "http://www.omg.org/spec/BPMN/20100524/MODEL");
        namespaceUris.put(BPMNDI, "http://www.omg.org/spec/BPMN/20100524/DI");
        namespaceUris.put(OMGDC, "http://www.omg.org/spec/DD/20100524/DI");
        namespaceUris.put(OMGDI, "http://www.omg.org/spec/DD/20100524/DC");
    }

    @Override
    public String getNamespaceURI(String prefix) {
        return namespaceUris.get(prefix);
    }
    @Override
    public String getPrefix(String namespaceURI) {
        return getKeyByValue(namespaceUris, namespaceURI);
    }
    @Override
    public Iterator<String> getPrefixes(String namespaceURI) {
        return getKeysByValue(namespaceUris, namespaceURI).iterator();
    }

    private static <T, E> Set<T> getKeysByValue(Map<T, E> map, E value) {
        Set<T> keys = new HashSet<T>();
        for (Entry<T, E> entry : map.entrySet()) {
            if (value.equals(entry.getValue())) {
                keys.add(entry.getKey());
            }
        }
        return keys;
    }

    private static <T, E> T getKeyByValue(Map<T, E> map, E value) {
        for (Entry<T, E> entry : map.entrySet()) {
            if (value.equals(entry.getValue())) {
                return entry.getKey();
            }
        }
        return null;
    }

}
